MONTPELIER — A national security author says the war on terrorism and the growth of digital technology are combining to increase the reach of government surveillance programs, even in Vermont.

Author William Arkin of Pomfret made the comments Tuesday during a conference on government surveillance hosted by the Vermont chapter of the American Civil Liberties Union in Montpelier.

But Arkin said even the people who are carrying out the surveillance aren’t sure how to balance the needs of privacy versus the needs of intelligence gathering, so there is room for members of the public to help put limits on that technology.

The conference follows a report released last month by Vermont ACLU about how many modern day conveniences, such as cellphones, make it possible for people to be tracked.

“The territory of freedom is shrinking,” Arkin said. “I do believe we are struggling to come up with rules of the road and to figure out how to behave in the information age.”

But at this point, there is hope, he added. The agencies collecting information are figuring it out too, and that means citizens can have an effect on creating such rules going forward.

Arkin, was one of the speakers at the ACLU’s daylong conference called “Surveillance on the Northern Border.” He began his career in Army intelligence in West Berlin during the Cold War. He helped report and write “Top Secret America,” a Washington Post investigation, and co-wrote a book of the same name.

Last month, the Vermont ACLU released a report outlining how the federal government plays a greater role in Vermont because it is a border state, though Arkin dismissed that designation.

“This physical geography is kind of old school,” he said. “Now we live in this virtual world, we live in this virtual world in which we are all connected.”

The Department of Homeland Security has a number of offices in Vermont, one of 16 border states. Many companies in the state work as contractors on security issues for the federal government.

“Everything becomes about national security and homeland security and our actual resilience and strength and vitality of our civil society and civil structures weaken under this aesthetic,” Arkin said.